kernel_optimize_test/drivers/md
Mike Snitzer aa6df8dd28 dm: fix free_rq_clone() NULL pointer when requeueing unmapped request
Commit 022333427a ("dm: optimize dm_mq_queue_rq to _not_ use kthread if
using pure blk-mq") mistakenly removed free_rq_clone()'s clone->q check
before testing clone->q->mq_ops.  It was an oversight to discontinue
that check for 1 of the 2 use-cases for free_rq_clone():
1) free_rq_clone() called when an unmapped original request is requeued
2) free_rq_clone() called in the request-based IO completion path

The clone->q check made sense for case #1 but not for #2.  However, we
cannot just reinstate the check as it'd mask a serious bug in the IO
completion case #2 -- no in-flight request should have an uninitialized
request_queue (basic block layer refcounting _should_ ensure this).

The NULL pointer seen for case #1 is detailed here:
https://www.redhat.com/archives/dm-devel/2015-April/msg00160.html

Fix this free_rq_clone() NULL pointer by simply checking if the
mapped_device's type is DM_TYPE_MQ_REQUEST_BASED (clone's queue is
blk-mq) rather than checking clone->q->mq_ops.  This avoids the need to
dereference clone->q, but a WARN_ON_ONCE is added to let us know if an
uninitialized clone request is being completed.

Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-30 10:25:21 -04:00
..
bcache md/bcache: use generic io stats accounting functions to simplify io stat accounting 2014-11-24 08:05:12 -07:00
persistent-data - Significant dm-crypt CPU scalability performance improvements thanks 2015-02-21 13:28:45 -08:00
bitmap.c md-cluster: re-add capabilities 2015-04-22 07:59:39 +10:00
bitmap.h md-cluster: re-add capabilities 2015-04-22 07:59:39 +10:00
dm-bio-prison.c dm bio prison: introduce support for locking ranges of blocks 2014-11-10 15:25:30 -05:00
dm-bio-prison.h dm bio prison: introduce support for locking ranges of blocks 2014-11-10 15:25:30 -05:00
dm-bio-record.h
dm-bufio.c dm bufio: fix time comparison to use time_after_eq() 2015-02-09 13:06:48 -05:00
dm-bufio.h
dm-builtin.c
dm-cache-block-types.h dm cache: revert "remove remainder of distinct discard block size" 2014-11-10 15:25:30 -05:00
dm-cache-metadata.c dm cache: fix missing ERR_PTR returns and handling 2015-01-28 09:59:20 -05:00
dm-cache-metadata.h dm cache: revert "remove remainder of distinct discard block size" 2014-11-10 15:25:30 -05:00
dm-cache-policy-cleaner.c
dm-cache-policy-internal.h
dm-cache-policy-mq.c dm cache policy mq: try not to writeback data that changed in the last second 2015-03-31 12:03:48 -04:00
dm-cache-policy.c
dm-cache-policy.h
dm-cache-target.c - Most significant change this cycle is request-based DM now supports 2015-02-12 16:36:31 -08:00
dm-crypt.c dm crypt: fix missing error code return from crypt_ctr error path 2015-04-16 22:00:50 -04:00
dm-delay.c dm delay: use msecs_to_jiffies for time conversion 2015-04-15 12:10:21 -04:00
dm-era-target.c
dm-exception-store.c
dm-exception-store.h
dm-flakey.c
dm-io.c dm io: deal with wandering queue limits when handling REQ_DISCARD and REQ_WRITE_SAME 2015-02-27 14:53:32 -05:00
dm-ioctl.c dm: only initialize the request_queue once 2015-04-30 10:25:21 -04:00
dm-kcopyd.c
dm-linear.c
dm-log-userspace-base.c dm log userspace base: fix compile warning 2015-04-15 12:10:20 -04:00
dm-log-userspace-transfer.c dm log userspace transfer: match wait_for_completion_timeout return type 2015-04-15 12:10:20 -04:00
dm-log-userspace-transfer.h
dm-log-writes.c dm: add log writes target 2015-04-15 12:10:24 -04:00
dm-log.c
dm-mpath.c dm: optimize dm_mq_queue_rq to _not_ use kthread if using pure blk-mq 2015-04-15 12:10:17 -04:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c
dm-raid1.c dm mirror: do not degrade the mirror on discard error 2015-02-13 19:50:46 -05:00
dm-raid.c - Most significant change this cycle is request-based DM now supports 2015-02-12 16:36:31 -08:00
dm-region-hash.c
dm-round-robin.c
dm-service-time.c
dm-snap-persistent.c dm snapshot: remove unnecessary NULL checks before vfree() calls 2015-02-09 13:06:49 -05:00
dm-snap-transient.c
dm-snap.c dm snapshot: suspend merging snapshot when doing exception handover 2015-02-27 14:53:16 -05:00
dm-stats.c - Significant DM thin-provisioning performance improvements to meet 2014-12-08 21:10:03 -08:00
dm-stats.h
dm-stripe.c dm stripe: fix potential for leak in stripe_ctr error path 2014-10-10 22:05:18 -04:00
dm-switch.c
dm-sysfs.c dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr 2015-04-15 12:10:17 -04:00
dm-table.c dm table: use bool function return values of true/false not 1/0 2015-04-15 12:10:23 -04:00
dm-target.c dm: allocate requests in target when stacking on blk-mq devices 2015-02-09 13:06:47 -05:00
dm-thin-metadata.c dm thin metadata: remove unused dm_pool_get_data_block_size() 2015-02-09 13:06:49 -05:00
dm-thin-metadata.h dm thin metadata: remove unused dm_pool_get_data_block_size() 2015-02-09 13:06:49 -05:00
dm-thin.c dm thin: fix to consistently zero-fill reads to unprovisioned blocks 2015-02-27 09:59:12 -05:00
dm-uevent.c
dm-uevent.h
dm-verity.c dm verity: add error handling modes for corrupted blocks 2015-04-15 12:10:22 -04:00
dm-zero.c
dm.c dm: fix free_rq_clone() NULL pointer when requeueing unmapped request 2015-04-30 10:25:21 -04:00
dm.h dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr 2015-04-15 12:10:17 -04:00
faulty.c md: rename ->stop to ->free 2015-02-04 08:35:52 +11:00
Kconfig md updates for 4.1 2015-04-24 09:28:01 -07:00
linear.c md: rename ->stop to ->free 2015-02-04 08:35:52 +11:00
linear.h
Makefile md updates for 4.1 2015-04-24 09:28:01 -07:00
md-cluster.c md-cluster: re-add capabilities 2015-04-22 07:59:39 +10:00
md-cluster.h md-cluster: re-add capabilities 2015-04-22 07:59:39 +10:00
md.c md: allow resync to go faster when there is competing IO. 2015-04-22 08:00:40 +10:00
md.h md: remove 'go_faster' option from ->sync_request() 2015-04-22 08:00:40 +10:00
multipath.c md: rename ->stop to ->free 2015-02-04 08:35:52 +11:00
multipath.h
raid0.c md raid0: access mddev->queue (request queue member) conditionally because it is not set when accessed from dm-raid 2015-04-22 08:00:41 +10:00
raid0.h
raid1.c md: remove 'go_faster' option from ->sync_request() 2015-04-22 08:00:40 +10:00
raid1.h md: make ->congested robust against personality changes. 2015-02-04 08:35:52 +11:00
raid5.c md/raid5: don't do chunk aligned read on degraded array. 2015-04-22 08:00:43 +10:00
raid5.h md/raid5: allow the stripe_cache to grow and shrink. 2015-04-22 08:00:43 +10:00
raid10.c md: remove 'go_faster' option from ->sync_request() 2015-04-22 08:00:40 +10:00
raid10.h md: make ->congested robust against personality changes. 2015-02-04 08:35:52 +11:00